Forcing me to become a concubine? Remarrying the Ninth Prince, she'll be pregnant all over the

On my reborn wedding day, the Crown Prince made my half-sister walk through the main gate, forcing me to become his concubine.
In my past life, I was born from his womb, and he had many children and grandchildren. Only on my deathbed did I learn that my child had been switched with hers by my closest relative!
In this life, I tore my wedding dress in public, turned around and grabbed the wrist of the Ninth Prince Wei Wujiu: "Marry me, and I will cure your old ailment and help you clean up the court."
He chuckled softly, "Deal."
Later, I saved his life with my miraculous healing techniques and helped him seize power with my wisdom.
When my half-sister faked a pregnancy again to win my favor, I diagnosed her as truly pregnant.
The court and the public were in an uproar—everyone said that the Ninth Prince was a eunuch, so whose child was this?
Wei Wujiu embraced me in front of everyone, looking down at the Crown Prince: "My wife is naturally carrying my legitimate son."
Those who stole my life and swapped my child, this time I will make them pay with their blood.